Settlement Advises

I was given a discount of 40% on my account.....once paid the Consultant at In-Quest Investigation advises that African Bank does not want to grant the 40% discount and will be sticking to a 30% discount as initially advised. Surely this is not ethical and totally unfair. Why wait until I settle as per the 40% settlement given to me in writing and then revert in saying that we are sorry but you still need to pay the balance of x because African Bank will only be granting the 30% discount. <br> I will not accept this! Please get someone in a senior position to contact me.